青豫直流工程入地电流对青海地区交流电网直流偏磁的影响  

Influence of Grounding Current of Qingyu DC Project on DC Bias of AC Grid in Qinghai Region

作　　者：李学鹏 李庆军 薛峰 王树潭 张万祥 陈奇 常伟 LI Xuepeng;LI Qingjun;XUE Feng;WANG Shutan;ZHANG Wanxiang;CHEN Qi;CHANG Wei(Northwest Electric Power Design Institute Co.,Ltd.of China Power Engineering Consulting Group,Xi’an,Shaanxi 710075,China;State Grid Qinghai Electric Power Company,Xining,Qinghai 810008,China;State Grid Qinghai Electric Power Construction Company,Xining,Qinghai 810008,China)

机构地区：[1]中国电力工程顾问集团西北电力设计院有限公司,陕西西安710075 [2]国网青海省电力有限公司,青海西宁810008 [3]国网青海省电力建设公司,青海西宁810008

出　　处：《广东电力》2021年第10期83-88,共6页Guangdong Electric Power

摘　　要：为了研究青豫直流工程投运后,青海海南换流站接地极入地电流对青海地区交流电网直流偏磁的影响,通过分析直流偏磁对交流电网的影响机理,以青海海南换流站接地极实测土壤电阻率及青海交流电网结构为基础,建立仿真模型对直流偏磁进行计算分析,并与换流站调试期间的交流电网直流偏磁的实测值进行比较。研究结果表明,变压器与接地极距离是影响直流偏磁幅值的主要因素。青豫直流工程单极大地运行期间,对于直流偏磁超过控制值10%以上的变压器,应重点关注单极大地运行期间,是否出现变压器噪音明显增加、振动或局部过热等现象,并据此判断是否采取安装隔直装置等直流偏磁抑制措施。In order to study the influence of the earth electrode grounding current of the Qinghai Hainan converter station on the DC bias of the AC grid in Qinghai after the Qinghai-Yu DC project is put into operation,the influence mechanism of the DC bias on the AC grid is analyzed,and based on the measured soil resistivity of the earth electrode and the structure of Qinghai AC power grid,a DC resistance network coupling model was established to calculate and analyze the DC bias,and compared with the actual measured value of the AC power grid during the commissioning of the converter station.The research results show that the distance to the earth electrode is the main factor that affects the DC bias amplitude.During HVDC ground return operation of the Qingyu DC project,for transformers whose DC bias exceeds the control value by more than 10%,attention should be paid to the operation period,Whether there is a significant increase in transformer noise,vibration or local overheating,etc.,and based on this,judge whether to take DC bias suppression measures such as installation of DC blocking devices.

关 键 词：接地极 变压器 直流偏磁 入地电流 

分 类 号：TM726[电气工程—电力系统及自动化] TM41